Exemplary embodiments of the present invention relate to a method for fabricating a semiconductor device, and more particularly, to a method for fabricating a storage node of a semiconductor device, which may reduce the occurrence of a bridge.
As an integration density of a semiconductor device increases, an area of a cell of the semiconductor device decreases. In particular, it becomes increasingly difficult to obtain a capacitance necessary for an operation of the semiconductor device including a capacitor (e.g., a dynamic random access memory (DRAM) device). In line with this trend, together with a thin film forming process for reducing a thickness of a dielectric layer, an attempt is continuously being made to increase the capacitance of the capacitor by forming a storage node (i.e., a bottom electrode of the capacitor) in a three-dimensional structure, for example, a cylindrical structure.
In order to form a cylindrical storage node, for example, a storage node hole is formed on a sacrificial dielectric pattern, and then a storage node layer is formed by forming a conductive material on the inner surface of the storage node hole, and performing an etching process. However, as the integration density of the semiconductor device increases, the interval between adjacent storage nodes decreases. This may cause a leaning phenomenon of the storage node, and thus a bridging phenomenon between the adjacent storage nodes may occur. In order to reduce the bridging phenomenon, a support pattern, e.g., a floating support pattern may be formed between the adjacent storage nodes by forming the support pattern on the sacrificial dielectric pattern between the adjacent storage nodes and removing the sacrificial dielectric pattern under the support pattern through a full dip-out process to form the floating support pattern.
However, during the full dip-out process, carbon and metal components, released from a metal layer constituting the storage node, may form a cluster and adhere to the top and bottom of the support pattern. The metal-carbon cluster may act as an electrical path between adjacent storage nodes.